#!/bin/bash

menu(){
	echo "#####################################"
	echo "1.display disk information"
	echo "2.show interface information"
	echo "3.show memory information"
	echo "4.exit" 
	read -p "please input your choice:" key
}
choice(){
	while :
	do
		clear
		menu
		case $key in
			1)
				df
				;;
			2)
				ip add
				;;
			3)
				free -m
				;;
			4)
				exit
				;;
			*)
				exit
				;;
		esac
		read  -n1 -p "please input any key to continue"
	done
}
